Then again, I guess it's best just to overlook it.
They might not have given it much thought. Just bored or something. That's pretty common in high school. Dumb actions,little thought.
And then again, they might have incredibly empty, pitiful lives if they're focusing on yours; someone they don't even know.
A more appropriate action for them-"Growing your hair out long? I don't think I'd want to fool with that."
Your comment sounds reasonable. Why to lose time and emotions for a reply to something that evidently has no substance.
In my environment (Munich, Germany) something like this don't happened to me yet, although sometimes people around me (at work) started two times a great discussion about their hair cut activities and how nice it looks and and and ... It is stopped now, it seems to be more important how my work and my personality is integrated into the project.
Sometimes childs make their joke, but I (and the hair) will survive it.
wolfgang